How do you connect pre-amps and power amps??

Discussion in 'Amps and Cabs [BG]' started by MODNY, Aug 25, 2005.

  1. MODNY

    MODNY Guest

    Nov 9, 2004
    I have a crest ca9 sitting here, and i'll be getting a pre-amp to go with her very soon..

    my question is, how exactly do you connect the 2 together??

    it has banana clips on the rear, aswell as XLR outputs


    pictures would be nice!
  2. Matt Call

    Matt Call Supporting Member

    Aug 1, 2004
    Minneapolis, MN
    You know, it's funny you're asking this... I was just wondering that as well. I'm sure it's simple, I just wouldn't want to risk anything.
  3. Munjibunga

    Munjibunga Total Hyper-Elite Member Gold Supporting Member

    May 6, 2000
    San Diego (when not at Groom Lake)
    Independent Contractor to Bass San Diego
    Preamp out to power amp in. There shouldn't be any XLR outputs on the back of the power amp ... those'd be inputs. It sounds like the connection to the speakers will be speakons or banana plugs out of the power amp. Make sure to RTFM on how to connect it if you're going to bridge. The output from the preamp may be either an XLR or TRS. Could be TS if it's a cheapie. What is it?
  4. Juniorkimbrough


    Mar 22, 2005
    Mississippi / Memphis, TN
    Endorsing Artist: Lakland Basses
    On my RBI > QSC RMX850, I just run a 1/4" instrument cable from the output on the RBI into the 1/4" input jack on the power amp. Then I have a banana plug run from the output on the power amp to my cab. Easy as pie.
  5. MODNY

    MODNY Guest

    Nov 9, 2004
    oh snap

    i just noticed that there is a 1/4 inch inputs on this puppy aswell.

    Ok, it says " in a" and there is a 1/4 inch jack ( pre-amp to power amp) then it says " out a" and there is banana plug

    so i should connect the OUT patch via a banana - speakon cable i would imagine..
  6. Juniorkimbrough


    Mar 22, 2005
    Mississippi / Memphis, TN
    Endorsing Artist: Lakland Basses
    yes, i have a cable that has a banana plug on one side and a 1/4" plug on the other end since I didn't want to hook my cab up with a banana plug.
  7. BillyB_from_LZ

    BillyB_from_LZ Supporting Member

    Sep 7, 2000
    Do you have a manual for the amp? If not, my guess is that you can get one from

    I let my fingers do the walkin' and came up with this...

    See page 13 for the juicy hook-up diagrams

    The North American version seems to be equipped with XLR and 1/4 in. jacks on the input and only 5-way binding posts (aka banana jacks) on the output.

    A short 1/4 in. to 1/4 in. instrument cable would be sufficient for interconnecting your preamp to the power amp. Be sure to follow the manual's instruction for setting the input switches.

    Have fun!!!!
  8. BillyB_from_LZ

    BillyB_from_LZ Supporting Member

    Sep 7, 2000
    The inputs (1/4 and XLR) are grouped together on the right side of the amp (as you face it from the back). "Out" on the input side is not a speaker level output (the manual doesn't show those markings).

    The speaker outputs are on the left side (again facing the back of the amp). They're clearly labeled.

    You have a top notch power amp there and would be wise to read the entire manual. If you can't bear to do that, focus on pages 11 and 12...
  9. MODNY

    MODNY Guest

    Nov 9, 2004


    my ca9 is a bit older then these new school ones. my selector switch ( for bridge, stereo and paralell) is inside.

    anyways... here's my back panel


    so if i'm right , by looking at the diagram listed on the crest manual (photo above) i connect the banana plugs ( hot and cold) to both hot outputs of each channel? ( pos. side of A and Pos. side of B) is this correct??

    also.. these dials on the front of the amplifier, do they control volume??
  10. softscrubmonkey


    Nov 19, 2004
    St. Louis
    sounds like you need to reconfigure the solar matrix in parrallel for endothermic propulsion :D
  11. MODNY

    MODNY Guest

    Nov 9, 2004

    how about i reconfigure your face :p
  12. Monomer


    Jul 22, 2005
    if your going to use a 1/4 plug, use TRS (TipRingSleeve) as this is a balenced connection, ensuring NO hum in the line caused by interconnects.

    Take the DI out (Low Z/ balenced) and run it to channel 1's input on the amp. set the (dip?) ( I own QSC) ont the amp to run bridged mono, and wire the speaker accordinly.

    And I'm sorry for all spelling mistakes made above. I just got off a very long day at work.
  13. BillyB_from_LZ

    BillyB_from_LZ Supporting Member

    Sep 7, 2000
    Assuming that you want to run the amp in the bridged mode, you'd set the internal switch to bridge, plug your preamp into input A and connect the loudspeaker across the two RED binding posts.

    I didn't read the manual, but I suspect that in the bridged mode, only the gain control for Channel A is active. And yes, it controls volume by controlling the gain of the power amp.

    If your future preamp has balanced outputs, you can use a balanced cable to the amp's input with either a 1/4 to 1/4 TRS (tip-ring-sleeve (aka "stereo" 1/4 in cable) cable, a short "mic" cable or one with 1/4 on one end, XLR on the other. If not, a short 1/4 to 1/4 in TS (tip-sleeve (aka "Mono" 1/4 in. cable) is just fine. In all cases, it must be shielded (not a speaker cable).

    Good luck!!!